嵌入式通信网络系统的抗毁性设计方法研究

嵌入式通信网络的运行环境复杂,降低了信息采集效率和通信网络协同控制任务性能。为了增强系统在复杂对抗环境下的协同性能,应提高系统的抗毁性。因此,采用LPC2290芯片作为微控制器,融合以太网模块、CAN模块、电源模块和相关外围接口模块,构建整个嵌入式通信网络系统。系统硬件电路结合子板和母板共同实现相关功能,提高系统的协同处理性能;采用基于Protocol_TCP协议的流套接子完成数据通信,增强通信系统的稳定性。依据嵌入式通信网络抗毁指标以及成本的最小化目标,设计网络抗毁性模型。将该抗毁性模型融入嵌入式通信网络自愈模型中,增强遭受攻击后网络的自愈能力,提高网络抗毁性能。实验结果表明,该设计系统具有较高的抗毁性,系统的吞吐量和平均时延性能较高。     

空间信息网络结构抗毁性优化设计

结合空间信息网络体系架构设计需求,提出了一种具有强抗毁性的空间信息网络结构设计方法。分析并选择自然连通度作为网络的抗毁性测度,提出了一种基于自然连通度的空间信息网络结构优化模型,设计了一种具有免疫审查的人工免疫算法并进行模型求解。仿真实验表明,在链路失效模式和节点失效模式下,优化设计的空间网络与典型空间信息系统相比具有更好的网络结构抗毁性与顽健性。     

机动干线通信网抗毁评估方法

机动干线通信网具有机动、灵活、多变性,对网络的抗毁性、可靠性、生存性有着特殊的要求。针对机动干线通信网的特点,提出一种快速评价网络整体抗毁性的方法,给出抗毁性定量计算的数学解析式,同时给出网络中各节点、链路对网络抗毁能力的贡献量度。建立合理、有效的抗毁量度指标对机动干线通信网络优化、网络调整以及网络评估都有着重要意义。     

复杂电磁环境下机动通信网络抗毁性评估

在建立机动通信网络模型的基础上,分析了复杂电磁对抗环境的基本构成,探讨了敌方可能的基于重要性指标的攻击目标选择策略。建立了电子对抗条件下模拟环境模型。再结合节点连通性、信道带宽、信道丢失率和平均时延等多项指标,建立了复杂电磁环境下机动通信网络抗毁性评估模型,并完成了抗毁性评估计算及仿真分析。     

网络分析与设计的抗毁性量度剖析

本文提出了一些用于网络分析与设计的抗毁性量度,通过一些网络例子对它们进行了分析和比较,并阐明了各种抗毁性量度的意义。文中论述了使用多种抗毁性量度的必要性及益处,同时也阐述了如何将抗毁性作为一个约束条件容扩到网络优化模型中。     

通信网络基于抗毁性的链路容量设计

本文定义了一种基于业务需求对的抗毁性量度，并且提出了一种相应的路径算法。在此基础上描述了通信网络基于抗毁性的链路容量设计方法。文中以一个８节点网络为例，给出了以该算法为基础的链路容量设计的计算机仿真结果。     

基于管理技术的ATM网络抗毁性研究

提出了基于管理技术的ATM网络抗毁性组织结构概念,指出了在网络规划设计与维护管理阶段进行层次化技术处理的重要性。ATM网络抗毁性组织结构要求在网络规划设计阶段、运用各种规划算法和仿真技术进行抗毁性设计与验证;在网络管理维护阶段,从网络各个层次,运用各种管理算法或机制维护网络抗毁性。在网络实际运行过程当中,该组织结构强调联合应用网络各层次上的抗毁性管理技术,充分发挥各个层次上的抗毁性,以提高整个网络抗毁性能。     

抗毁通信网设计方法的探讨

本文详细论述了一种新的组网过程模型,考虑的因素包括网络性能、地形复杂度、距离因子、抗毁性、电磁兼容性、资源最佳利用等方面,并提出一种在网络设计过程中考虑抗毁性的方法。     

关于概率网络可靠性的一种评估方法

论文主要针对概率网络,提出了一种评估其可靠性的指标,给出了其数学解析式。在文章最后假定了概率网络的一个实例模型并且对其进行了可靠性分析。该指标考虑到了通信节点间数据交换的不对称性;网络拓扑结构和它的时变性;网络链路和节点的不可靠性以及网络的迂回路由问题,能够简单、直观地反应整个概率网的可靠性和抗毁性。     

通信网络拓扑抗毁性评估算法研究

首先论述了当前主要网络拓扑抗毁性评估技术,然后根据实际工程应用需求,提出了一种新的通信网络拓扑抗毁性评估模型与算法,同时用计算机对模型和算法进行了仿真验证。该算法能求出通信网络拓扑图中各节点抗毁性度量值以及这些度量值的均方差,且把节点抗毁性度量值均方差作为整个网络拓扑的抗毁性量度。计算机仿真结果表明,利用该模型算法可以发现拓扑图中关键节点,同时度量值均方差可以准确评估给定连通网络拓扑图的抗毁性能。     

空间通信中的网络可靠性分析

为研究空间通信网络的可靠性,首先介绍了空间通信环境特点及通信网络的可靠性理论基础,然后讨论了通信网络的可靠性评价指标,包括抗毁性、生存性、有效性及其计算方法。由于网络可靠性评估涉及的因素较多且相互影响,采用建立网络可靠性模型方法以研究网络部件失效及修复的情况,应用概率分析方法得到系统可靠性的数学模型,并给出了系统可靠性与节点和链路可靠性的关系,可供空间网设计参考。     

通信网生存性设计中分集路由的影响分析

对宽带通信网进行生存性设计十分重要。网的生存性与包括路由在内的诸多因素有关,本文分析分集路由的分割因子对网生存性和费用的影响,发现均匀分割因子对网的生存性和费用的影响十分独特,从而为网的生存性设计提供了有益的参考。     

基于UCDS的战术网络拓扑构建研究

在战术MANET中,底层通信的拓扑结构是不断变化的。寻找最小连通子图(作为一个网络拓扑结构的主干)是在MANET的MAC层设计中网络拓扑构建的有效方法。在战术网络环境下研究用于广播的连通支配集构建算法,阐述了一种分布式的连通支配集算法(UCDS),该算法采用启发式规则选取支配节点及其连接节点。通过与其他相关研究对比分析,表明UCDS具有实施简单、执行速度快、消息复杂度低的特点,同时具备一定的灵活和抗毁能力,并能够实际应用于路由优化和低速率下节点的移动自适应。     

Optimized design of survivable MPLS over optical transport networks

In this paper we study different options for the survivability implementation in MPLS over Optical Transport Networks (OTNs) in terms of network resource usage and configuration cost. We investigate two approaches to the survivability deployment: single-layer survivability, where some recovery mechanism (e.g. protection or restoration) is implemented in a single network layer and multilayer survivability, where recovery is implemented in multiple network layers. The survivable MPLS over OTN design is implemented as a static network optimization problem and incorporates various methods for spare capacity allocation (SCA) to reroute disrupted traffic.The comparative analysis between the single layer and the multilayer survivability shows the influence of the traffic granularity on the survivability cost: for high-bandwidth LSPs, close to the optical channel capacity, the multilayer survivability outperforms the single layer one, whereas for low-bandwidth LSPs the single-layer survivability is more cost-efficient. For the multilayer survivability we demonstrate that by mapping efficiently the spare capacity of the MPLS layer onto the resources of the optical layer one can achieve up to 22% savings in the total configuration cost and up to 37% in the optical layer cost. Further savings (up to 9%) in the wavelength use can be obtained with the integrated approach to network configuration over the sequential one; however, this is at the increase in the optimization problem complexity. These results are based on a cost model with current technology pricing and were obtained for networks targeted to a nationwide coverage.     

带有生存性感知的低成本光无线混合网络无线功能部署策略

光无线混合网络的生存性保障程度与部署成本之间存在矛盾。为提高网络资源利用率,该文提出一种低成本的无线功能部署策略。根据网络中无线功能部署情况,综合考虑网络生存性保障程度及部署成本两方面因素,在此基础上,提出基于向量评价的二进制粒子群算法实现其优化过程,进而,由进化得到的种群粒子不断调整光网络单元选取,以较低的成本实现较强生存性的网络部署。结果表明所提出的无线功能部署策略能有效提高网络的生存性,并大幅度的降低网络成本。     

飞机生存力设计技术评价及选择方法研究

介绍了一种评价和选择飞机生存力设计技术的方法。首次从敏感性和易损性两个方面提出了飞机生存力的评价指标体系,构建了生存力设计技术对评价指标的影响矩阵;用协商定权方法确定各评价指标的权重,并通过影响矩阵评价生存力设计技术对提高生存力的作用。因为生存力提高是以增加重量和费用为代价的,提出了"单位费用单位重量获得的生存力"的概念来评价和选择飞机生存力设计技术。最后,通过实例分析了飞机生存力设计技术评价和选择的过程。     

Survivable MPLS Over Optical Transport Networks: Cost and Resource Usage Analysis

In this paper we study different options for the survivability implementation in MPLS over optical transport networks (OTN) in terms of network resource usage and configuration cost. We investigate two approaches to the survivability deployment: single layer and multilayer survivability and present various methods for spare capacity allocation (SCA) to reroute disrupted traffic. The comparative analysis shows the influence of the offered traffic granularity and the physical network structure on the survivability cost: for high bandwidth LSPs, close to the optical channel capacity, the multilayer survivability outperforms the single layer one, whereas for low bandwidth LSPs the single layer survivability is more cost-efficient. On the other hand, sparse networks of low connectivity parameter use more wavelengths for optical path routing and increase the configuration cost, as compared with dense networks. We demonstrate that by mapping efficiently the spare capacity of the MPLS layer onto the resources of the optical layer one can achieve up to 22% savings in the total configuration cost and up to 37% in the optical layer cost. Further savings (up to 9 %) in the wavelength use can be obtained with the integrated approach to network configuration over the sequential one, however, at the increase in the optimization problem complexity. These results are based on a cost model with different cost variations, and were obtained for networks targeted to a nationwide coverage     

Some approaches to solving a multihour broadband network capacity design problem with single-path routing

In this paper, we consider solution approaches to a multihour combined capacity design and routing problem which arises in the design of dynamically reconfigurable broadband communication networks that uses the virtual path concept. We present a comparative evaluation of four approaches, namely: a genetic algorithm, a Lagrangian relaxation based subgradient optimization method, a generalized proximal point algorithm with subgradient optimization, and, finally, a hybrid approach where the subgradient based method is combined with a genetic algorithm. Our computational experience on a set of test problems of varying network sizes services) shows that the hybrid approach often is the desirable choice in obtaining the minimum cost network while the genetic algorithm based approach has the most difficulty in solving large scale problems. This revised version was published online in June 2006 with corrections to the Cover Date.     

Cross-layer optimization with cooperative communication for minimum power cost in packet error rate constrained wireless sensor networks

This paper addresses the problem of joint design of routing, medium access control (MAC), and physical layer protocols with cooperative communication to achieve minimum power cost in packet error rate (PER) constrained wireless sensor networks (WSNs). The problem is solved in two steps. First, we calculate the minimum power cost with a specified PER objective between any two nodes, assuming either cooperative (with a single relay node) or direct communication between the two nodes. It is shown that the minimum per-hop power cost is found in 2M and log₂ M steps for cooperative and direct communication, respectively, where M is the number of power levels. Second, we formulate the cross-layer design problem as a linear optimization problem to minimize the power cost of the whole network, using the minimum per-hop power cost determined in the first step as input and assuming time division multiple access (TDMA) at the MAC layer. Numerical results show that, at a desired end-to-end PER objective, cross-layer optimization with cooperative communication achieves up to 70% of power savings compared to that without cooperative communication.